Motor attachment for sewing-machines and the like.



G B. JOHNSON. MOTOR ATTACHMENT FOR SEWING MACHINES AND THE LIKE.APPLICATION FILED APR. 10, 1909.

933,710, v Patented Sept. 7, i909.

' fi yi.

UNITED STATES PATENT. OFFICE.

CARL JOHNSON, OF LOS ANGELES, CALIFORNIA, ASSIGNOR OF ONE-HALF 'IOWILLIAM W. PIDDINGTON, OF LOS ANGELES, CALIFORNIA.

MOTOR ATTACHMENT FOR SEWING-MACHINES AND THE LIKE.

Specification of Letters Patent.

Patented Sept. 7, 1909.

Application filed April 10, 1909. Serial No. 489,212.

To all whom it may concern:

Be it known that I, CARL E. JoHNsoN,a citizen of the United States,residing at Los Angeles, California, have invented a new and usefulMotor Attachment for Sewing- Machines and the Like, of which thefollowing is a specification.

' This invention relates to an improved means for attaching an electricmotor to the treadle of a sewing machine or other treadle operatedmachine.

An object of the invention is to provide an attachment of the characterstated which may be readily applied to various'desi s of sewing machinesnow on the market wlthout the necessity of altering the construction ofthe sewing machine itself.

Another object is to provide a motor attachment adapted for beingattached to the' machine in a osition where said attachment will be outof the way and also out of sight where it will not hinder the operationof the machine or detract from the appearance of the machine.

A further object is to provide for connecting the motor with the machinein such a manner that the operator by simply varying pressure upon thetreadle may conveniently vary. the speed of the machine.

The invention further relates to an improved treadle-operated means forcontrolling the electric switch.

Other advantages may hereinafter appear.

Referring to the accompanying drawings which illustrate theinvention,l*igure 1 is an end elevation of a sewing machine providedwith the attachment. Fig. 2 is a plan view of the motor and means forattaching the same to the machii'ie, a fragment of the treadle beingshown. Fig. 3 is a face view of the circuit closing device, the coverthere of being removed. In this view the motor is indicateddiagrammatically. Fig. 4 is a face view of the opposite side of Fig. 3.Fig. 5 is a transverse section on line x of Fig. 3.

Referring in detail to the drawings,-The motor 1 is provided with aflanged pedestal 2 which is attached to the base plate 3 by means ofbolts 5 and nuts 6, the motor thus being mounted upon the treadle toswing on an axis coincidental with the treadle pivot 3. In order to makea yielding, non-conducting. connection between said pedestal 2 and baseplate 3, rubber washers 6 are interposed between said pedestal and baseplate around the bolts 5 as shown in Fig. 1. 6 are like washers betweenthe heads of said bolts and the upper side of said pedestal 2. Said baseplate 3 is attached at its front end to the pedal 7 by bolts 8, providedwith nuts 9, and thus supports the motor somewhat to the rear of thepedal.

11 is a clampln plate through which the bolts 8 extend an which isplaced between the nuts 9 and the lower side of the treadle 7.Ordinarily the treadle of the sewing ma chine is formed of grill-work asshown in Fig. 2 so that the base plate 3 may be clamped thereto as shownin Figs. 1 and 2 without the necessity of drilling any holes through thetreadle.

The motor is rovided with a driving pulley 12 moved into and out ofoperative engagement with the drivin belt 13 which passes over thedriving whee 14 of the sewing machine.

15 is a tension spring tending to raise the. rear end of the treadle soas to slacken the belt 13 and withdraw the pulley of the motor fromoperative engagement therewith when it is desired to stop the machine.Said spring 15 is illustrated as suspended by a rod 16 from a hook-16made fast to the top board 16 of the design of sewing machineillustrated in the drawings, but it is to be understood that said springmay be attached in various ways as may be found most convenient on othermachines.

15 designates a pin or stud projecting from the end of the motor toprovide an attachment from the lower end of spring 15.

In order to turn the electric current on and off from. the motor,circuit closing device 17 is provided furnished with terminals 18 and19. To the circuit closing device 17 ispivotcd an arm 21 ofnon-conducting material by a pivot stud 22. The inner end of said armcarries a resilient circuit making member having an arm 23 adapted toengage the stationary terminal 18 and an arm 24 adapted to engage theterminal 19 at the same time that the arm 23 engages the terminal 18.Said circuit making member preferably consists. of a strip of phosphorbronze, but may be composed of any other spring metal. The angularportion of said spring member is desirably attached to the arm 21 bybeing seated in grooves 25 shown in Fig. 5. 26 designates a wire springtending to maintain the switch open by holding said arm 21 in theposition shown in full lines in Fig.3.

The current may be led from an ordlnary light socket a through the cordb'through the aperture 0. One wire d of the cord b leads to thebindingpost: e and thence to the terminal 19'. The other wire f leads tothe binding post it, thence to the motor 1, the circuit being completedby a wire 18 which connects the motor with the terminal 18.

' To, the outer end of arm 21 is attached a coiled tension spring 27.The upper end of said spring is suspended from some stationary part ofthe machine preferably by being fastened to the lower end of the rod 16.

In operation, when the operator depresses the rear end of the treadle 7the circuit closing device-17 moves downwardly and the tension uponspring 27 increases to overcome the tension of spring 26 so that thelever 21 is thrown to the position shown in dotted lines in Fig. 3 thusmaking a circuit from the terminal 1.9 to the terminal 18 through thecircuit making arms 23 and 24, thus putting the motor into operation.This action is effected by a slight movement of the treadle 7. Upon afurther movement of the treadle the belt 13 is tightened upon thedriving pulley 12 so that the motor, which has already been started,will turn the wheel 14 operating the machine.

One of the advantages of making contact by means of the spring arms 23and 24 is that said arms, as the treadle is fully depressed, slidesomewhat across the pins 18 and 19 after they come in contact with saidpins thus automatically cleaning the contact points.

In operating the device, if the operator desires to run the machine atless than full speed she will apply but a slightpressure to the treadleand will not draw the driving belt '13 so tightly across the drivingpulley 12 but that said belt will slide somewhat along the groove ofsaid pulley and will not drive the machine at so great a speed as whensaid belt is drawn taut.

lVhile the invention is not limited to the use of any specific electricmotor, it is nevertheless desirable that a motor be employed which has agood starting torque, preferably a series wound motor.

The flanges 12 of the motor pulley 12 are made of considerable length soas to be sufficiently large to prevent the belt 13, when slackened, frombecoming disengaged from the pulley.

18 is the wire leading from the switch to the terminal 18. 21 is a pinforming a stop to engage the upper side of the arm 21.

I claim:

1. The" combination, with a machine having a treadle and a driving wheellocated above said treadle, of an electric motor mounted on said treadleto swing on an axis coincidental with the pivot thereof, yielding meanstending to raise that end of said treadle, said motor being providedwith a driving pulley, a belt extending around the driving wheel of themachine and said driving pulley, and means for making and breaking theelectric circuit through said motor;

2. The combination, with a machine having a driving wheel and a treadletherebeneath, of an electric motor mounted on said treadle at one sideof the pivot thereof, yielding means tending to raise that end of saidtreadle, a switch mounted on said treadle to open and close circuitthrough said motor, a connection leading from said switch up to astationary part of said machine to close said switch when the treadle isdepressed, said motor being provided with a driving pulley, and means tooperatively connect said pulley with said driving wheel of the machine.

3. In combination, a machine, a treadle adapted to operate the same, anelectric motor mounted on said treadle, means operatively connectingsaid motor with said machine, a switch mounted on said treadle to openand close circuit through said motor, and a connection leading from saidswitch to a stationary nart of said machine to operate said switch by amovement of said treadle.

4. In a device of the character described, the combination, with themachine, treadle, motor mounted on said treadle, and means foroperatively connecting said motor with said machine; of a switch forsaid motor comprising stationary terminals, a contact making memberprovided with spring arms adapted to simultaneously engage saidterminals, a pivoted arm carrying said contact making member, a springto normally hold said arm in position to maintain open circuit, and aconnection leading from said arm toa stationary part of said machine toclose the circuit by a movement of the treadle.

5. In combination, a machine, a treadle mounted thereon, an electricmotor mounted on said treadle, means to operatively connect said motorwith said machine, automatic means normally maintaining said motor in aninoperative condition, a circuit closing device in the circuit of saidmotor, automatic means for maintaining said circuit closing device in aninoperative condition, and means for operating said circuit closingdevice and motor by a movement of the treadle.

6. In a device of the character described,

the combination with the machine and treadle electric switch mounted onsaid treadle to control the circuit through said motor, a connectionbetween said switchand machine to cause an initial movement of saidtreadle to 5 close said switch and a further movement of said treadle toautomatically clean the contact making elements.

'8. In a device of the character described,

the combination, with an electric motor, a

10 machine operated by said motor, and a treadle mounted 011 saidmachine; of a circuit closing device to control said motor said devicebeing mounted on said treadle, and a connection extending fromi saiddevice to a sta- 5 tionary part of said machine to cause a cuit closingdevice.

9. In a device of the character described, the combination, with anelectric motor, a

movement of said treadle to operate said cir- 20 machine operated bysaid motor and a treadle mounted on said machine; of a switch to controlsaid motor comprising stationary terminals, a contact making memberconsisting of a pair of spring arms formed in a single piece,

treadle and connected to a stationary part of the machine, to providefor operating said switch by a movement of said treadle.

In testimony whereof I have hereunto signed my name in the presence oftwo subscribing witness% at Los Angeles, in the county of Los Angelesand State of California, this fifth day of April 1909.

CARL E. JOHNSON. Witnesses:

ALBERT H. MERRILL, 'FLORA H. Foss.

